What are the health risks of consuming Nitrate water with high concentrations of nitrate? Nitrate levels greater than 10 ppm exceed state and federal standards for nitrate in public drinking water supplies. No infant or any female who is or may become pregnant In should consume any water that exceeds this standard (either by drinking or by eating foods prepared with the water such as soups, juices, and coffee). Additionally, the Drinking Wisconsin Department of Health Services recommends that all people avoid long-term consumption of water that has a nitrate level greater than 10 ppm. Water In infants under 6 months of age ingestion How does nitrate enter groundwater? of nitrate can reduce the blood’s ability to carry oxygen. In severe cases it can In nature, water usually contains less than 1 cause a condition that doctors call milligram of nitrate-nitrogen per liter and is not methemoglobinemia. The condition is also This brochure explains how nitrate can enter considered a health concern. Significantly higher called “blue baby syndrome” because the drinking water supplies, the health effects of nitrate concentrations can indicate that the infant’s skin appears blue-gray or lavender in nitrate exposure, when to test a private well, drinking water has been contaminated and color. This skin color change is caused by a and things you can do to reduce the nitrate may pose a serious health concern. Common lack of oxygen in the blood. level in your drinking water. The brochure also sources of nitrate include nitrogen fertilizers, All infants less than 6 months of age are at risk of nitrate provides sources of information and assistance manure, septic systems and sewage treatment toxicity, but premature babies and babies with other that may be useful to private well owners. practices. Nitrate dissolves easily in water and does health problems are more sensitive than healthy infants. not adsorb onto the soil. It can easily be carried into An infant suffering from “blue baby syndrome” needs What is nitrate? the groundwater by rainwater and melting snow as immediate medical care because the condition can lead they percolate through the soil and bedrock into the to coma and death if it is not treated promptly. Nitrate (NO −) is a compound made up of nitrogen underlying aquifer. 3 When nursing mothers ingest water containing elevated and oxygen. It is formed when nitrogen from Is my well at risk? concentrations of nitrate, the amount of nitrate in breast ammonia or other sources combines with oxygen milk may increase slightly. Although no confirmed cases in water. Nitrate is naturally found in plants and in of “blue baby syndrome” have been associated with The only way to know if your drinking water contains vegetables at varying concentrations. It is often in nitrate in breast milk, it may be advisable for nursing excessive nitrate is to have a water sample analyzed groundwater depending on the amount of fertilizer and women to avoid drinking water that contains more than by a certified laboratory. There are also several things manure applied to crop fields. According to the U.S. 10 milligrams of nitrate per liter of water. Environmental Protection Agency, most adults who are you can check to determine your well’s vulnerability to eating a balanced diet may consume 10-25 milligrams nitrate contamination. Some scientific studies have also found evidence of an association between exposure to high nitrate levels in of nitrate-nitrogen per day in their food. Most of Well Location. Nitrate-contaminated wells are often drinking water during the first weeks of pregnancy and this nitrate comes from leafy vegetables like lettuce, located near farm fields, barnyards, feedlots, septic certain birth defects; further scientific study is needed to cabbage, celery, spinach, and cured meats. Additional tanks, municipal wastewater treatment systems or confirm this association. exposure to nitrate from contaminated drinking water “sludge” spreading sites. may pose a significant health risk. Well casing depth and construction. Since nitrate Some researchers suspect that consuming enters the aquifer from the ground surface, wells that nitrate-contaminated water may increase the The Wisconsin Department of Natural Resources Bureau of have shallow casing are more likely to be affected than risk of thyroid disease, diabetes, and certain Drinking Water and Groundwater would like to thank the deeper cased wells. types of cancer. People who have heart Groundwater Coordinating Council (GCC) Education Sub- or lung disease, certain inherited enzyme Geology. Areas with highly porous, sandy soils, Committee for its part in the development and editing of this defects or cancer may be more sensitive to the toxic fractured bedrock, natural caves and sinkholes, publication. For more information on the GCC, it’s member effects of nitrate than healthy individuals. organizations and programming, please visit wisconsin.gov. and shallow depths to groundwater are especially Choose “Government,” “State Agencies,” followed by “List of vulnerable to contamination. Areas with highly Wells contaminated with high nitrate levels are more Agencies” then select “Groundwater Coordinating Council.” exposed creviced bedrock or specific geologic likely to be contaminated with agricultural pesticides. If conditions known as “karst” limestone geology, your water is contaminated with nitrate, you may want Wisconsin Department of Natural Resources present in much of Door County for example, may also to have the water tested for pesticides, especially if your Bureau of Drinking Water & Groundwater be vulnerable to nitrate contamination. well is near farm fields. How do I know if my water What should I do if Where can I get more Contact Us is safe to drink? my water is high information? in nitrate? Customer Service Staff are here to assist you. Public Water Systems Licensed well drillers can help you How may we help you? All public water systems are required to notify determine whether drilling a well If the nitrate-nitrogen Call Toll Free 1-888-WDNRINFO (1-888-936-7463) consumers if any regulated contaminant, including with more casing can reduce the concentration of your water Or, go to dnr.wi.gov, Search: Contact nitrate, exceeds the maximum contaminant level nitrate levels in your water. Check exceeds the 10-milligram per Click on one of the following options: (MCL) that is set by the federal Safe Drinking liter standard, the following your local phone directory under Water Act. Municipal systems (such as city, town, actions are recommended: “Water Well Drilling & Service.” Chat with customer service. or sanitary districts) and Other-Than-Municipal The Wisconsin Department of Call a representative. (OTM) systems (such as mobile home parks or No infant or female who is or may become pregnant Health Services (DHS), Division of Email your question. condominium associations) are required to report Public Health can give you more any detection of a regulated contaminant that should consume any water Toll free hotlines that exceeds 10 ppm nitrate. information on the potential health occurred in the previous year in their annual effects of nitrate exposure. Call Violation Hotline: The Wisconsin Division of Consumer Confidence Report (CCR). If you would (608) 266-1120 or visit the DHS 1-800-TIP-WDNR or Public Health recommends like to view your community’s CCR, contact website at dhs.wisconsin.gov/water. phone 1-800-847-9367 your local water supplier or visit the Wisconsin that people of all ages avoid Confidentially report Department of Natural Resources (DNR) website long-term consumption The Wisconsin Department of suspected wildlife, at dnr.wi.gov, Search: water quality data. Then of water that has a nitrate Agriculture, Trade and Consumer recreational and select Drinking Water Sample Results. A search level greater than 10 ppm. Protection (DATCP) can give you environmental can then be made by city or individual system. Do not attempt to more information on locating violations. remove the nitrate by potential nitrate sources. Treatment methods are available Call (608) 224-4502 or visit the Emergency that can reduce the levels of nitrate boiling the water. This Spill Hotline: will only increase the DATCP website at datcp.state.wi.us in the drinking water supply, 1-800-943-0003 phone but some methods may be more nitrate concentration. A list of certified labs is available appropriate or cost-effective than Seek medical help online at dnr.wi.gov, Search: others. In many cases the best option immediately if the skin certified labs. Bilingual Services are available for a community is to drill a new well. color of an infant appears DNR has more information about Drinking Water & Groundwater Program bluish or gray. Sometimes drinking water on its website. Go 101 S. Webster Residential Well Owners color change is first noticed to dnr.wi.gov, Search: drinking P.O. Box 7921 around the mouth, or The only way to know if your drinking water water, and select from a variety of Madison, WI 53707-7921 on the hands and feet. contains nitrate is to have a water sample from listed topics. Find out how to deal (608) 266-1054 your private well tested by a certified laboratory. Protect your water supply with water quality problems by For more information, go to dnr.wi.gov, A list of certified labs is available online at from nitrate contamination searching for “What’s Wrong with Search: Drinking Water dnr.wi.gov, Search: certified labs. A nitrate test is by reducing fertilizer you My Water” on the DNR website. use, improving manure- recommended for all newly constructed private The University of Wisconsin- wells and wells that have not been tested during handling methods, maintaining your septic Cooperative Extension has many the past 5 years. Testing is also recommended publications related to drinking water for well water used by pregnant women and is system and pumping septic tanks regularly and water quality available on its essential for a well that serves infants under 6 The Wisconsin Department of Natural Resources to prevent overflow.